After making some small changes on my project, this file came up generated in WEB-INF. I don't know how it got generated (maybe by JBoss tools?) but afer redeploying my app to JBoss 5.1.0, the application keeps getting redeployed in an infinite loop until the app server crashes with an OutOfMemoryException. Deleting it, all goes fine...

Hmm, so I guess the only way to get rid of this problem is to modify the ant build script to delete this file in case it exists... Ok, thank's a lot. I was only afraid that this file might actually have some relevance at runtime and deleting it might cause some problems.